In situ construction of hollow carbon spheres with N, Co, and Fe co-doping as electrochemical sensors for simultaneous determination of dihydroxybenzene isomers

作者：Hui Yang, Shunxing Li, Huiwu Yu, Fengying Zheng, Luxiu Lin, Jie Chen, Yuehai Li, Ye Lin · 发表于：Nanoscale · 年份：2019 · DOI：10.1039/c9nr01146c · 被引用次数：46 · 研究领域：Conducting polymers and applications、Electrochemical Analysis and Applications、Electrochemical sensors and biosensors

Control of the active sites/centers plays an important role in the design of novel electrode materials with unusual properties and achievement of sensors with high performance. In this study, three-dimensional (3D) freestanding multi-doped hollow carbon spheres (N-Co-Fe-HCS) with a layer thickness of 30 nm, which contained multiple active sites of the heteroatom N and transition metals (Co and Fe), were synthesized via a simple template method (with SiO2 as the template) and cost-efficient in situ self-polymerization, self-adsorption/reduction and carbonization strategies. Moreover, a series of hollow carbon sphere composites of the same family (N-HCS, N-Co-HCS and N-Fe-HCS) were prepared by this sensible process using the same method and precursors but different doping elements. These differences lead to different active sites/centers from hollow carbon spheres and improved electrocatalytic activities for dihydroxybenzene isomers. Furthermore, N-Co-Fe-HCS as an electrochemical sensor exhibited excellent simultaneous qualitative and quantitative determination performance for catechol (CC) and hydroquinone (HQ). The detection limit and the linear range were 75 nmol L-1 and 0.5-500 μmol L-1 for CC and 80 nmol L-1 and 0.5-1500 μmol L-1 for HQ, respectively. The interference from the components coexisting in river water on the detection of CC and HQ was not observed. These results indicate that high-performance electrochemical sensors can be constructed by in situ multi-element d...